How to Solve the Automatic Door Locking Issue of Dongfeng Tianlong?

[Garrett]

First, disconnect the negative terminal of the battery for a period of time, wait for the engine's protection data to clear, and then reconnect it. Generally, a power disconnection of about 10 seconds is sufficient. Call for a tow truck and it is recommended to go to the designated 4S dealership, where a fault decoder might easily resolve the issue.

[DeCamilla]

I previously drove a Dongfeng Tianlong and also encountered the issue of the doors locking themselves. Several times, I got locked out and had to use the spare key. After a lot of troubleshooting, I found the problem was a small motor in the main driver's door lock assembly that had failed. This motor controls the locking mechanism, and when it ages, it can malfunction. When I took it apart myself, I found the connector was clogged with mud. Cleaning it temporarily solved the issue. Anyone who drives trucks long-term knows that dust easily gets into the door joints, especially for vehicles operating on construction sites. Every time I wash the truck, I use a toothbrush to clean the door seams, which keeps the problem at bay for about half a year. If all else fails, I go to the service center to replace the entire door lock actuator for about 600 RMB—much better than constantly getting locked out and delaying work.

[MacHarley]

While delivering auto parts in my friend's Tianlong truck, I suddenly heard a loud 'click' and all the doors automatically locked, which gave me quite a scare. The mechanic advised me to first check the fuse box—that black box under the driver's seat. Using a test light, I checked each fuse one by one and sure enough, found a blown one. It only cost five yuan to replace the fuse, but you have to make sure the specs and model match exactly. The mechanic said issues like this are often caused by wiring short circuits. Tracing the wiring harness along the door hinge, I found exposed wires touching the metal. He suggested wrapping the door frame wiring harness with anti-abrasion tape during the rainy season, as mud and water seeping in can easily cause short circuits.

[Robert]

During my last long-distance trip, I noticed the doors were locking unexpectedly. It turned out to be a stuck signal switch inside the door handle. The mechanic at the service station explained that Dongfeng door locks come with speed sensing and automatically lock above 15 km/h, which is quite common. However, when the switch doesn't return to its position, the system thinks you're constantly trying to open the door. The solution is to remove the interior trim panel and spray some WD-40 lubricant on the lock linkage. This issue is particularly frequent in the seven-seater passenger version of the Tianlong, as the rear doors are used more often. By the way, a friendly reminder: avoid placing coins in the door slots, as coins getting stuck in the mechanical parts can also mistakenly trigger the locking mechanism.